Basic freehand controls of the dual-action airbrush
Basic Airbrush Control Techniques
It is not easy to learn to use the airbrush from a live or video demonstration. It's impossible for the student to see the delicate finger movements that control the airbrush. Also, the airbrush teacher is hard pressed to give a "play-by-play" description of his actions because the actions occur in far less time than it takes to describe them. For beginners, static diagrams and images are better methods for describing basic control the airbrush. The following images illustrate the basic airbrush control techniques that every new airbrush artist will need to learn.
Cone Shaped Spray Pattern
The pattern of paint coming from the tip of an airbrush is conical in shape. The atomized droplets are more concentrated near the tip of the airbrush and they become more disperse as they move farther away. This factor is a critical feature of all airbrushes. An airbrush artist makes strokes on an art surface by moving the airbrush across the surface while releasing paint. If the artist holds the airbrush several inches away, the stroke will be broad and pale. If the artist keeps the tip of the airbrush near the art surface the spray pattern will be narrow and dense. It's possible to make pencil-thin lines by holding the airbrush very close to art surface.
The diagram below illustrates the difference in stroke patterns created by varying distance.
Single-action airbrushes require the artist to preset the paint flow volume prior to pressing the button (sometimes called a trigger) that turns the air on. The artist has to stop spraying if he wants to change the volume. Dual-action airbrushes offer a great advantage. Dual-action allows the artist to vary the volume of paint released with the same button that turns the air on or off. Pressing the button down turns the air on and pulling the button back (while keeping the air on) releases paint. The more the button is pulled back, the more paint is released. Returning the button forward reduces the volume released. The artist can do this "on the fly" without having to stop spraying.
The diagram below illustrates the difference in stroke patterns created by varying volume.
Speed of motion has to be taken into consideration when learning to airbrush. Making strokes slowly will deposit more paint than moving rapidly over the same space. Also, moving more quickly tends to smooth out the contours of each stroke.
The diagram below illustrates the difference in stroke patterns created by varying speed of motion.
How to learn to control all three elements at the same time
A skilled airbrush artist has learned to coordinate all three control elements at the same time. The easiest way to learn to control each element is to isolate one at a time. This allows the artist to clearly see the effect of each individual control. For example, keeping the distance control and speed control constant or steady and varying only the volume control allows the artist to concentrate on the volume control only. The same technique can be used for the other controls. To concentrate on distance control, take care to keep the volume and speed control constant and vary distance only. Of course, for speed control, keep the volume and distance constant and vary only the speed control.
The diagram below illustrates examples of isolated control elements.
Speed is essential
Notice in the diagram above, speed had the least effect in the spray pattern. Even though it's the least obvious, it is probably the most important to master. Try this demonstration. Hold the airbrush at a steady distance and volume and draw a circle very slowly, say in 5 seconds. Now draw the same size circle as quickly as you can. It's likely that neither circle is perfect, however the one drawn quickly will have smooth contours and will be more appealing.
Have you ever noticed how Tshirt artists always appear to be in a rush? Granted they want to work as quickly as possible, but the real reason for their rapid motion is to produce nicely contoured lines and tones. It takes a long time to learn to airbrush with quick strokes and that is not to imply that learning the other controls is easy. Nevertheless, mastering rapid motion is crucial when it comes to producing well-formed lines and smooth, even tones.
There are other factors that effect spray patterns, but distance, volume and speed are the basics. As in all creative endeavors practice is the key to success. Learning to use the airbrush freehand is very challenging. It can be very rewarding as well, as the airbrush is probably the most versatile of all the artist's tools. A highly skilled airbrush artist can duplicate almost any other painting style, from abstract to photo realism.
I will post more Hubs on airbrushing. There's a lot more to learn, especially the technical and trouble shooting aspects.